SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd69db3f6df8dfcb51f8247409599201d78f18056f67a5e2a3ea133a13957010e' 
  AND token = 'KWvgHaYhqGthRalU8mvzByfBLYIt4DbcTqmy2CY4ZOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}